Monoaminofluorene compound and organic light-emitting device using the same

ABSTRACT

Novel monoaminofluorene compounds are provided, and organic light-emitting devices which exhibit good luminescence hue of extremely high purity and have optical output with high luminescence efficiency, high luminance and longer operating life are provided using the compounds. The monoaminofluorene compound represented by the following general formula [1]:

TECHNICAL FIELD

The present invention relates to a monoaminofluorene compound and anorganic light-emitting device, more particularly to a light-emittingdevice using an organic compound which emits light by applying anelectric field to a thin film of the organic compound.

BACKGROUND ART

An organic light-emitting device is a device having a thin filmcontaining a fluorescent organic compound interposed between an anodeand a cathode, in which excitons of the fluorescent compound aregenerated by injecting electrons and holes (positive holes) from eachelectrode into the compound and the light emitted when these excitonsreturn to the ground state is utilized.

In a research by Eastman Kodak Company in 1987 (Appl. Phys. Lett. 51,913 (1987)), luminescence on the order of 1000 cd/m² upon application ofvoltage on the order of 10 V was reported in relation to a device havinga function separate type two-layer structure using ITO for the anode,and magnesium silver alloy for the cathode, respectively, and usingaluminum quinolinol complex as an electron-transporting material as wellas a light-emitting material and triphenylamine derivative as ahole-transporting material. Relevant patents include U.S. Pat. Nos.4,539,507, 4,720,432, 4,885,211, etc.

Moreover, luminescence ranging from ultraviolet to infrared rays can beobtained by changing the kind of fluorescent organic compound, and,recently, studies on various compounds are actively conducted. Forexample, such studies are described in U.S. Pat. Nos. 5,151,629,5,409,783, 5,382,477, Japanese Patent Application Laid-Open No.2-247278, Japanese Patent Application Laid-Open No. 3-255190, JapanesePatent Application Laid-Open No. 5-202356, Japanese Patent ApplicationLaid-Open No. 9-202878, Japanese Patent Application Laid-Open No.9-227576, etc.

In addition to the organic light-emitting devices using low molecularmaterials as mentioned above, an organic light-emitting device using aconjugated polymer was reported by a group in Cambridge University(Nature, 347, 539 (1990)). This report confirms that luminescence occursin a single layer film which is formed of poly(phenylene vinylene) (PPV)using a coating system. Related patents of the organic light-emittingdevice using conjugated polymer include U.S. Pat. Nos. 5,247,190,5,514,878, 5,672,678, Japanese Patent Application Laid-Open No.4-145192, Japanese Patent Application Laid-Open No. 5-247460, etc.

The latest progress in the organic light-emitting device is remarkablein this way, and the features thereof facilitate production oflight-emitting devices imparted with high luminance at low appliedvoltage, diversity of luminescence wavelength, high-speed response, thinshape and lightweight, thereby suggesting possibility for a wide varietyof applications.

However, there still remain many problems in respect of durability, suchas change with the passage of time by prolonged use, degradation byatmospheric gas containing oxygen, humidity, etc. Furthermore, when theapplication to a full color display and the like is envisaged, opticaloutput of further higher luminance or higher conversion efficiency, andluminescence in blue, green and red of high color purity are requiredunder the present condition.

For example, although diamine compounds as a luminescent material weredisclosed in Japanese Patent Application Laid-Open No. 2001-52868, blueluminescence of high color purity (chromaticity coordinate: x,y=0.14-0.15, 0.09-0.10) was not obtained. An example using a compoundhaving the similar diamino structure was also disclosed in JapanesePatent Application Laid-Open No. 2001-196177, but the compound was usedas a hole injection layer, and there was no description of the use as alight-emitting layer and light-emitting properties thereof such asluminescence color and efficiency.

DISCLOSURE OF THE INVENTION

The present invention has been made to solve these problems of the priorart, and an object of the present invention is to provide a novelmonoamino compound.

Another object of the present invention is to provide an organiclight-emitting device exhibiting good luminescence hue of extremely highpurity and high luminance optical output with a high efficiency and alonger operating life.

Still another object of the present invention is to provide an organiclight-emitting device which can be readily manufactured at relativelylow cost.

The inventors of the present invention conducted intensive study inorder to solve the above-mentioned problems and came to complete thepresent invention.

That is, the monoaminofluorene compound of the present invention ischaracterized in that it is represented by the following general formula[1] or [2].

wherein X₁ is a divalent group selected from the group consisting ofsubstituted or unsubstituted alkylene, aralkylene, arylene andheterocyclic ring groups, and alkylene, aralkylene, alkenylene, amino,silyl, carbonyl, ether and thioether groups having a linking groupconsisting of a substituted or unsubstituted arylene or divalentheterocyclic ring group, or X₁ may be a direct bond;

X₂ is a group selected from the group consisting of a hydrogen atom, ahalogen group, substituted or unsubstituted alkyl, aralkyl, alkenyl,alkynyl, alkoxy, aryl, heterocyclic ring and sulfide groups, asubstituted silyl group and a cyano group;

Y₁ and Y₂ may be the same or different and are groups selected from thegroup consisting of substituted or unsubstituted alkyl, aralkyl, aryland heterocyclic ring groups, substituted or unsubstituted alkylene,aralkylene, alkenylene, amino and silyl groups having a linking groupconsisting of a substituted or unsubstituted arylene or divalentheterocyclic ring group, and unsubstituted carbonyl, ether and thioethergroups having a linking group consisting of a substituted orunsubstituted arylene or divalent heterocyclic ring group;

Y₁ and Y₂, or X₁, Y₁ and Y₂ may also join together to form a ring;

R₁ and R₂ may be the same or different and are groups selected from thegroup consisting of a hydrogen atom, and substituted or unsubstitutedalkyl, aralkyl and aryl groups; and

n is an integer of 2 to 10 when X₁ is a direct bond and X₂ is a hydrogenatom, and otherwise an integer of 1 to 10.

wherein X₃ and X₄ may be the same or different and are divalent groupsselected from the group consisting of a substituted or unsubstitutedalkylene, aralkylene, arylene and heterocyclic ring groups, substitutedor unsubstituted alkylene, aralkylene, alkenylene, amino and silylgroups having a linking group consisting of a substituted orunsubstituted arylene or divalent heterocyclic ring group, unsubstitutedcarbonyl, ether and thioether groups, or X₃ may be a direct bond;

X₅ is a group selected from the group consisting of a hydrogen atom, ahalogen group, substituted or unsubstituted alkyl, aralkyl, alkenyl,alkynyl, alkoxy, aryl, heterocyclic ring and sulfide groups, asubstituted silyl group, and a cyano group;

Y₃ and Y₄ may be the same or different and are groups selected from thegroup consisting of substituted or unsubstituted alkyl, aralkyl, aryland heterocyclic ring groups, substituted or unsubstituted alkylene,aralkylene, alkenylene, amino and silyl groups having a linking groupconsisting of a substituted or unsubstituted arylene or divalentheterocyclic ring group, and unsubstituted carbonyl, ether and thioethergroups having a linking group consisting of a substituted orunsubstituted arylene or divalent heterocyclic ring group;

Y₃ and Y₄, or X₃, Y₃ and Y₄ may also join together to form a ring;

R₃ to R₆ may be the same or different and are groups selected from thegroup consisting of a hydrogen atom, and substituted or unsubstitutedalkyl, aralkyl and aryl groups; and

each of p and q is an integer not less than one and p+q is an integer of2 to 10.

In the organic light-emitting device of the present invention comprisinga pair of electrodes which consist of an anode and a cathode and one ormore layers which are interposed between the electrodes and contain anorganic compound, the at least one layer containing the organic compoundpreferably contains at least one compound represented by theabove-mentioned general formula [1] or [2].

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a cross-sectional view showing an example of the organiclight-emitting device according to the present invention;

FIG. 2 is a cross-sectional view showing another example of the organiclight-emitting device according to the present invention;

FIG. 3 is a cross-sectional view showing another example of the organiclight-emitting device according to the present invention;

FIG. 4 is a cross-sectional view showing another example of the organiclight-emitting device according to the present invention;

FIG. 5 is a cross-sectional view showing another example of the organiclight-emitting device according to the present invention; and

FIG. 6 is a cross-sectional view showing another example of the organiclight-emitting device according to the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention will be described in detail below.

The monoaminofluorene compound of the present invention is describedfirst.

The monoaminofluorene compound of the present invention is representedby the above-mentioned general formula [1] or [2].

The monoaminofluorene compound of the present invention can mainly beused as an organic light-emitting device material, and when it is usedas a light-emitting device material, devices having high color purity,high luminescence efficiency and a longer operating life canrespectively be obtained even in a single layer. Furthermore, aluminescence spectrum with a narrower half-value width, i.e.,luminescence more excellent in color purity is obtained by introducingfluorene having a rigid structure into the main chain of the molecule.Furthermore, since the Stokes shift is suppressed, a shift of theluminescence wavelength is suppressed, and it is also possible to shiftthe absorption even toward a longer wavelength side, and when it is usedas a dopant material, use of a host material which has a luminescencespectrum in a relatively longer wavelength side is also enabled.

Each of the monoaminofluorene compounds of the present invention can beused for the purpose of both dopant material and host material in alight-emitting layer to provide a device having high color purity, highluminescence efficiency, and longer operating life, and in particularcan be used as a dopant material in combination with a suitable hostmaterial of easily causing energy transfer to provide a device holdinghigh color purity luminescence and having higher efficiency.

Specific examples of the substituents in the above-mentioned generalformulae [1] and [2] are shown below.

Examples of the substituted or unsubstituted linear or cyclic alkylgroup include methyl group, ethyl group, n-propyl group, n-butyl group,n-hexyl group, n-decyl group, iso-propyl group, iso-butyl group,tert-butyl group, tert-octyl group, trifluoromethyl group, cyclohexylgroup, cyclohexylmethyl group, but, of course, are not limited to these.

Examples of the substituted or unsubstituted aralkyl group includebenzyl group, phenethyl group, but, of course, are not limited to these.

Examples of the substituted or unsubstituted aryl group include phenylgroup, 4-methylphenyl group, 4-methoxyphenyl group, 4-ethylphenyl group,4-fluorophenyl group, 3,5-dimethylphenyl group, triphenylamino group,biphenyl group, terphenyl group, naphthyl group, anthracenyl group,phenanthrenyl group, pyrenyl group, tetracenyl group, pentacenyl group,fluorenyl group, triphenylenyl group, perylenyl group, but, of course,are not limited to these.

Examples of the substituted or unsubstituted heterocyclic ring groupinclude pyrrolyl group, pyridyl group, bipyridyl group, methylpyridylgroup, terpyrrolyl group, thienyl group, terthienyl group, propylthienyl group, furyl group, quinolyl group, carbazolyl group, oxazolylgroup, oxadiazolyl group, thiazolyl group, thiadiazolyl group, but, ofcourse, are not limited to these.

Examples of the substituted or unsubstituted alkylene group includemethylene group, ethylene group, propylene group, iso-propylene group,butylene group, tert-butylene group, hexylene group, heptylene group,cyclohexylene group, cyclohexylmethylene group, but, of course, are notlimited to these.

Examples of the substituted or unsubstituted aralkylene group includebenzylene group, phenylethylene group, phenethylene group, but, ofcourse, are not limited to these.

Examples of the substituted or unsubstituted arylene group includephenylene group, biphenylene group, 2,3,5,6-tetrafluorophenylene group,2,5-dimethylphenylene group, naphtylene group, anthracenylene group,phenanthrenylene group, tetracenylene group, pentacenylene group,perylenylene group, but, of course, are not limited to these.

Examples of the substituted or unsubstituted divalent heterocyclic ringgroup include furanylene group, pyrrolylene group, pyridinylene group,terpyridinylene group, thiophenylene group, terthiophenylene group,oxazolylene group, thiazolylene group, carbazolylene, but, of course,are not limited to these.

Examples of the substituted or unsubstituted alkenyl group include vinylgroup, allyl group (2-propenyl group), 1-propenyl group, iso-propenylgroup, 2-butenyl group, but, of course, are not limited to these.

Examples of the substituted or unsubstituted amino group include aminogroup, methylamino group, ethylamino group, dimethylamino group,diethylamino group, methylethylamino group, benzylamino group,methylbenzylamino group, dibenzylamino group, anilino group,diphenylamino group, phenyltolylamino group, ditolylamino group,dianisolylamino group, but, of course, are not limited to these.

Examples of the substituted or unsubstituted carbonyl group includeacetyl group, propionyl group, isobutyryl group, methacryloyl group,benzoyl group, naphtoyl group, anthranyl group, toluoyl group, but, ofcourse, are not limited to these.

Examples of the substituted or unsubstituted alkoxy group includemethoxy group, ethoxy group, propoxy group, 2-ethyl-octyloxy group,phenoxy group, 4-butylphenoxy group, benzyloxy group, but, of course,are not limited to these.

Examples of the substituted or unsubstituted sulfide group includemethylsulfide group, ethylsulfide group, phenylsulfide group,4-methylphenylsulfide group, but, of course, are not limited to these.

Examples of the substituent group which the above-mentioned substituentgroups may have include alkyl groups such as methyl group, ethyl group,n-propyl group, iso-propyl group, ter-butyl group, octyl group, benzylgroup and phenethyl group, an aralkyl group, alkoxy groups such asmethoxy group, ethoxy group, propoxy group, 2-ethyl-octyloxy group,phenoxy group, 4-butylphenoxy group and benzyloxy group, aryl groupssuch as phenyl group, 4-methylphenyl group, 4-ethylphenyl group,3-chlorophenyl group, 3,5-dimethylphenyl group, triphenylamino group,biphenyl group, terphenyl group, naphthyl group, anthryl group,phenanthryl group and pyrenyl group, a heterocyclic ring group such aspyridyl group, bipyridyl group, methylpyridyl group, thienyl group,terthienyl group, propylthienyl group, furyl group, quinolyl group,carbazolyl group and N-ethylcarbazolyl group, a halogen group, cyanogroup, and nitro group, but, of course, are not limited to these.

Typical examples of the compound represented by the general formulae [1]and [2] are shown below but are not limited to these compounds.

TABLE 1 n R1, R2 X1 X2 Y1 Y2 1 1 Me Direct bond Ph Ph Ph 2 1 Me Directbond Ph

3 1 Me Direct bond Ph Ph

4 1 Me Direct bond Ph Ph

5 1 Me Direct bond Ph Ph

6 1 Me Direct bond Ph Ph

7 1 Me Direct bond Ph Ph

8 1 Me Direct bond Ph Ph

9 1 Me Direct bond

10 1 Me Direct bond

11 1 Me Direct bond

12 1 Me Direct bond

13 1 Me

H Ph Ph 14 1 Me

H

15 1 Me

H Ph

16 1 Me

H Ph

17 1 Me

H Ph

18 1 Me

H Ph

19 1 Me

Ph Ph Ph 20 1 Me

Ph

TABLE 2 R1, n R2 X1 X2 Y1 Y2 21 1 Me

Ph Ph

22 1 Me

Ph Ph

23 1 Me

24 1 Me

25 1 Me

Ph

26 1 Me

27 1 Me

28 1 Me

Ph

29 1 Me

H

30 1 Me

H

31 1 Me

32 1 Me

H

33 1 Me

H

34 1 Me

H

35 1 Me

36 1 Me

H

TABLE 3 R1, n R2 X1 X2 Y1 Y2 37 1 Me

H

38 1 n-Bu

H

39 1 n-Bu

40 1 Ph

H

41 1 Ph

42 2 Me Direct bond H Ph Ph 43 2 Me Direct bond H

44 2 Me Direct bond H

45 2 Me Direct bond H Ph

46 2 Me Direct bond H Ph

47 2 Me Direct bond H Ph

48 2 Me Direct bond H Ph

49 2 Me Direct bond H Ph

50 2 Me Direct bond H Ph

51 2 Me Direct bond Ph

52 2 Me Direct bond Ph Ph

53 2 Me Direct bond Ph Ph

54 2 Me Direct bond Ph Ph

55 2 Me Direct bond

56 2 Me Direct bond

TABLE 4 n R1, R2 X1 X2 Y1 Y2 57 2 Me Direct bond

58 2 Me Direct bond

59 2 Me

H Ph Ph 60 2 Me

H

61 2 Me

H

62 2 Me

H Ph

63 2 Me

H Ph

64 2 Me

H Ph

65 2 Me

H Ph

66 2 Me

H Ph

67 2 Me

H Ph

68 2 Me

H Ph

69 2 Me

Ph Ph Ph 70 2 Me

Ph

71 2 Me

Ph Ph

72 2 Me

Ph Ph

73 2 Me

Ph Ph

74 2 Me

75 2 Me

76 2 Me

Ph

TABLE 5 n R1, R2 X1 X2 Y1 Y2 77 2 Me

78 2 Me

79 2 Me

Ph

80 2 Me

H

81 2 Me

H

82 2 Me

83 2 Me

H

84 2 Me

H

85 2 Me

H

86 2 Me

87 2 Me

H

88 2 Me

H

89 2 n-Bu

H

90 2 n-Bu

91 3 Me Direct bond H Ph Ph 92 3 Me Direct bond H

93 3 Me Direct bond H Ph

94 3 Me Direct bond H Ph

TABLE 6 n R1, R2 X1 X2 Y1 Y2 95 3 Me Direct bond H Ph

96 3 Me Direct bond H Ph

97 3 Me Direct bond H Ph

98 3 Me Direct bond H Ph

99 3 Me Direct bond H Ph

100 3 Me Direct bond H

101 3 Me Direct bond H

102 3 Me Direct bond Ph Ph

103 3 Me Direct bond Ph Ph

104 3 Me Direct bond Ph Ph

105 3 Me Direct bond

106 3 Me Direct bond

107 3 Me Direct bond

108 3 Me Direct bond

109 3 Me

H

110 3 Me

H Ph

111 3 Me

H Ph

112 3 Me

H Ph

113 3 Me

H Ph

114 3 Me

H Ph

TABLE 7 R1, n R2 X1 X2 Y1 Y2 115 3 Me

Ph

116 3 Me

117 3 Me

118 3 Me

Ph

119 3 Me

120 3 Me

Ph

121 3 Me

H

122 3 Me

H

123 3 Me

124 3 Me

H

125 3 Me

H

126 3 Me

H

127 3 Me

128 3 Me

H

129 3 Me

H

130 3 n-Bu

H

131 3 n-Bu

TABLE 8 n R1, R2 X1 X2 Y1 Y2 132 3 Me Direct bond H Ph Ph 133 3 MeDirect bond H

134 3 Me Direct bond H Ph

135 3 Me Direct bond H Ph

136 3 Me Direct bond H Ph

137 3 Me Direct bond H Ph

138 3 Me Direct bond H Ph

139 3 Me Direct bond H Ph

140 3 Me Direct bond H Ph

141 3 Me Direct bond H

142 4 Me

H

143 4 Me

H Ph

144 4 Me

H Ph

145 4 Me

146 4 Me

147 4 Me

Ph

148 4 Me

H

149 4 Me

H

150 4 Me

H

TABLE 9 n R1, R2 X1 X2 Y1 Y2 151 4 Me

H

152 4 Me

H

153 4 Me

H

154 4 n-Bu

H

155 4 n-Bu

[1]-156

[1]-157

[1]-158

[1]-159

[1]-160

[1]-161

[2]

TABLE 10 p, q R3, R4 R5, R6 X3 X4 X5 Y3 Y4 1 1, 1 Me Me Single bond

H Me Ph 2 1, 1 Me Me Single bond

H Ph Ph 3 1, 1 Me Me Single bond

H

4 1, 1 Me n-Bu Single bond

H

5 1, 1 n-Bu n-Bu Single bond

H

6 1, 1 Me Me Single bond

H

7 1, 1 Me Me Single bond

H

8 1, 1 Me Me Single bond

H Ph

9 1, 1 Me Me Single bond

H Ph

10 1, 1 Me Me Single bond

H Ph

11 1, 1 Me Me Single bond

H Ph

12 1, 1 Me Me Single bond

H Ph

13 1, 1 Me Me Single bond

H Ph

14 1, 1 Me Me Single bond

H Ph

15 1, 1 Me Me Single bond

H

16 1, 1 Me Me Single bond

H Ph

17 1, 1 Me Me Single bond

H

18 1, 1 Me Me Single bond

H Ph

19 1, 1 Me Me Single bond

H

20 1, 1 Me Me Single bond

H Ph

21 1, 1 Me Me Single bond

H

TABLE 11 p, q R3, R4 R5, R6 X3 X4 22 1, 1 Me Me Single bond

23 1, 1 Me Me Single bond

24 1, 1 Me Me Single bond

25 1, 1 Me Me Single bond

26 1, 1 Me Me Single bond

27 1, 1 Me Me Single bond

28 1, 1 Me Me Single bond

29 1, 1 Me Me Single bond

30 1, 1 Me Me Single bond

31 1, 1 Me Me Single bond

32 1, 1 Me Me Single bond

33 1, 1 Me Me Single bond

34 1, 2 Me Me Single bond

35 1, 2 Me Me Single bond

36 1, 2 Me Me Single bond

37 1, 2 Me Me Single bond

38 1, 2 Me Me Single bond

39 1, 2 Me Me Single bond

40 1, 1 Me Me

41 1, 1 Me Me

42 1, 1 Me Me

X5 Y3 Y4 22 H Ph

23 H

24 H Ph

25 H

26 H

27 H Ph

28 H

29 H Ph

30 H

31 H Ph

32 H

33 H

34 H

35 H Ph

36 H Ph

37 H Ph

38 H

39 H

40 H

41 H

42 H

TABLE 12 p, q R3, R4 R5, R6 X3 X4 43 1, 1 Me Me

44 1, 1 Me n-Bu

45 1, 1 n-Bu n-Bu

46 1, 1 Me Me

47 1, 1 Me Me

48 1, 1 Me Me

49 1, 1 Me Me

50 1, 1 Me Me

51 1, 1 Me Me

52 1, 1 Me Me

53 1, 1 Me Me

54 1, 1 Me Me

55 1, 1 Me Me

56 1, 1 Me Me

57 1, 2 Me Me

58 1, 2 Me Me

59 1, 1 Me Me Single bond

60 1, 1 Me Me Single bond

61 1, 1 Me Me Single bond

62 1, 1 Me Me Single bond

X5 Y3 Y4 43 H

44 H

45 H

46 H

47 H

48 H

49 H

50 H

51 H

52 H

53 H

54 H

55 H

56 H

57 H

58 H

59 Ph

60

61

62

TABLE 13 p, q R3, R4 R5, R6 X3 X4 X5 63 1, 1 Me Me Single bond

64 1, 1 Me Me Single bond

65 1, 1 Me Me

Ph 66 1, 1 Me Me

67 1, 1 Me Me

68 1, 1 Me Me

69 1, 1 Me Me

70 1, 1 Me Me

71 2, 2 Me Me Single bond

H 72 2, 2 Me Me Single bond

H 73 2, 2 Me Me Single bond

H 74 2, 2 Me n-Bu Single bond

H 75 2, 2 n-Bu n-Bu Single bond

H 76 2, 2 Me Me Single bond

H 77 2, 2 Me Me Single bond

H 78 2, 2 Me Me Single bond

H 79 2, 2 Me Me Single bond

H 80 2, 2 Me Me Single bond

H 81 2, 2 Me Me Single bond

H 82 2, 2 Me Me Single bond

H 83 2, 2 Me Me Single bond

H 84 2, 2 Me Me Single bond

H Y3 Y4 63

64

65

66

67

68

69

70

71 Me Ph 72 Ph Ph 73

74

75

76

77

78 Ph

79 Ph

80 Ph

81 Ph

82 Ph

83 Ph

84 Ph

[2]-85

[2]-86

[2]-87

Next, the organic light-emitting device of the present invention will bedescribed in detail.

The organic light-emitting device of the present invention is an organiclight-emitting device comprising: a pair of electrodes which consist ofan anode and a cathode, and one or more layers which are interposedbetween the electrodes and contain an organic compound, wherein at leastone layer of the layers containing an organic compound contains at leastone of the monoaminofluorene compounds represented by theabove-mentioned general formula [1] or [2].

Moreover, it is preferable that the layer containing the compoundrepresented by the above-mentioned general formula [1] or [2] containsat least one of the compounds represented by following general formulae[3] to [7], and it is more preferable that the layer containing thecompound represented by the above-mentioned general formula [1] or [2]is a light-emitting layer.

wherein Ar₁ to Ar₃ may be the same or different and are groups selectedfrom the group consisting of substituted or unsubstituted aryl andheterocyclic ring groups, and either one of them may be a hydrogen atom,a substituted or unsubstituted alkyl group, or a substituted orunsubstituted aralkyl group; and R₇ to R₉ are groups selected from thegroup consisting of a hydrogen atom, a halogen group, substituted orunsubstituted alkyl and aralkyl groups, a substituted amino group and acyano group.

wherein Ar₄ to Ar₇ may be the same or different and are groups selectedfrom the group consisting of substituted or unsubstituted aryl andheterocyclic ring groups; and R₁₀ and R₁₁ are groups selected from thegroup consisting of a hydrogen atom, a halogen group, substituted orunsubstituted alkyl and aralkyl groups, a substituted amino group and acyano group.

wherein Ar₈ to Ar₁₂ may be the same or different and are groups selectedfrom the group consisting of substituted or unsubstituted aryl andheterocyclic ring groups; and R₁₂ is a group selected from the groupconsisting of a hydrogen atom, a halogen group, substituted orunsubstituted alkyl, aralkyl, aryl and heterocyclic ring groups, asubstituted amino group and a cyano group.

wherein Ar₁₃ to Ar₁₆ may be the same or different and are groupsselected from the group consisting of substituted or unsubstituted aryland heterocyclic ring groups, and up to any three of them may be ahydrogen atom, a halogen group, a substituted or unsubstituted alkylgroup and a substituted or unsubstituted aralkyl group; and R₁₃ to R₁₆are groups selected from the group consisting of a hydrogen atom, ahalogen group, substituted or unsubstituted alkyl, aralkyl, aryl andheterocyclic ring groups, a substituted amino group and a cyano group.

wherein R₁₇ and R₁₈ are groups selected from the group consisting of ahydrogen atom and substituted or unsubstituted alkyl, aralkyl and arylgroups, and R₁₇'s and R₁₈'s bound to different fluorene moieties may bethe same or different and R₁₇ and R₁₈ bound to the same fluorene moietymay be the same or different; R₁₉ to R₂₂ are groups selected from thegroup consisting of a hydrogen atom, a halogen group, substituted orunsubstituted alkyl and aralkyl and alkoxy groups, a substituted silylgroup and a cyano group; and s is an integer of 2 to 5.

Although the compounds represented by general formulae [3] to [7] can beused for the purpose of both the dopant material and host material in alight-emitting layer respectively to obtain a device with high colorpurity, high luminescence efficiency and longer operating life, a deviceholding high color purity luminescence and having even higherluminescence efficiency can be obtained with the combination of acompound represented by the general formula [1] or [2] as a dopantmaterial with a suitable host material which easily causes energytransfer, for example, the compounds represented by general formulae [3]to [7]. The dopant concentration in the host material is preferably from0.01% to 50% by weight, more preferably from 0.5% to 10% by weight.

Specific examples of the substituents in general formulae [3] to [7] arethe same as those referred to in the above-mentioned general formulae[1] and [2]. Typical examples of the compound represented by generalformulae [3] to [7] are given below but the present invention is notlimited to these.

The preferable examples of the organic light-emitting device of thepresent invention are shown in FIGS. 1 to 6.

FIG. 1 is a cross-sectional view showing an example of the organiclight-emitting device according to the present invention. FIG. 1 shows astructure in which an anode 2, a light-emitting layer 3 and a cathode 4are formed on a substrate 1 in this order. The light-emitting deviceused here is useful in the case where it has all the properties ofhole-transporting ability, electron-transporting ability and thelight-emitting ability by itself, or in the case where compounds havingeach of these properties respectively are mixed and used.

FIG. 2 is a cross-sectional view showing another example of the organiclight-emitting device according to the present invention. FIG. 2 shows astructure in which an anode 2, a hole-transporting layer 5, anelectron-transporting layer 6 and a cathode 4 are formed on a substrate1 in this order. This structure is useful in the case where alight-emitting material having either one or both of hole-transportingability and electron-transporting ability is used for the respectivelayer in combination with a hole-transporting or electron-transportingcompound which has no light-emitting properties. A light-emitting layer3 consists of either the hole-transporting layer 5 or theelectron-transporting layer 6 in this case.

FIG. 3 is a cross-sectional view showing another example of the organiclight-emitting device of the present invention. FIG. 3 shows a structurein which an anode 2, a hole-transporting layer 5, a light-emitting layer3, an electron-transporting layer 6 and a cathode 4 are formed on asubstrate 1 in this order. Since this structure separates the functionsof carrier transport and luminescence, it can be used in a suitablecombination with compounds having hole-transporting ability,electron-transporting ability and light-emitting ability, thus extremelyenhancing the flexibility of selection of materials and enabling variouscompounds which differ in luminescence wavelength to be used, therebyenabling diversification of luminescence hue. Furthermore, it alsobecomes possible to effectively confine each of the carriers or excitonsin the light-emitting layer 3 positioned in the middle, and to aim atimprovement in luminescence efficiency.

FIG. 4 is a cross-sectional view showing another example of the organiclight-emitting device of the present invention. FIG. 4 shows a structurein which a hole injecting layer 7 is inserted in the side of an anode 2as compared with that of FIG. 3 and that has an effect in improving theclose contact of the anode 2 and a hole-transporting layer 5 orimproving hole injecting properties and is effective for reduction involtage.

FIGS. 5 and 6 are cross-sectional views showing other examples of theorganic light-emitting device of the present invention. FIGS. 5 and 6show structures in which a layer inhibiting holes or excitons fromescaping to the side of a cathode 4 (hole blocking layer 8) is insertedbetween a light-emitting layer 3 and an electron-transporting layer 6,in comparison with the structures of FIGS. 3 and 4. By using a compoundhaving a very high ionization potential as the hole blocking layer 8,these structures are effective for improving the luminescenceefficiency.

However, FIGS. 1 to 6 merely show very fundamental device structures,and the construction of the organic light-emitting device using thecompound of the present invention is not limited to these. For example,various layer configurations can be taken including providing aninsulating layer on the interface between the electrode and the organiclayer, providing an adhesive layer or interference layer, or making ahole-transporting layer consisting of two layers different in ionizationpotential.

The monoaminofluorene compound represented by the general formula [1] or[2] used for the present invention can be used in any embodiment ofFIGS. 1 to 6.

Especially the organic layer using the compound of the present inventionis useful as a light-emitting layer, an electron-transporting layer or ahole-transporting layer, and the layer formed by the vacuum evaporationmethod, the solution applying method or the like is excellent instability with the passage of time since crystallization thereof cannotreadily take place.

Although the present invention uses the monoaminofluorene compoundrepresented by the general formula [1] or [2] particularly as acomponent of a light-emitting layer, it can also be used, if needed,together with a hole-transporting compound, a luminescent compound or anelectron-transporting compound known in the art.

Examples of these compounds are given below.

Hole-transporting Compound

Electron-transporting Light-emitting Material

Light-emitting Material

Matrix Material of Light-emitting Layer and Electron-transportingMaterial

Hole-transporting Polymer Material

Light-emitting and Electron-transporting Polymer Material

In the organic light-emitting device of the present invention, the layercontaining the monoaminofluorene compound represented by the generalformula [1] or [2] and the layer consisting of other organic compoundscan be generally formed into a thin film by the vacuum evaporationmethod or by the applying method by dissolving the compounds in asuitable solvent. When film forming is conducted especially by theapplying method, the film can also be formed in combination with asuitable binding resin.

The above-mentioned binding resin can be selected from a wide range ofbinding resins and examples thereof include poly(vinyl carbazole) resin,polycarbonate resin, polyester resin, polyallylate resin, polystyreneresin, acrylic resin, methacrylic resin, butyral resin, poly(vinylacetal) resin, diallyl phthalate resin, phenol resin, epoxy resin,silicone resin, polysulphone resin, urea resin, etc. but are not limitedto these. These resins may be used alone or mixed as a copolymerizedpolymer of one or more types of them.

As an anode material, those having as high a work function as possibleis suitable, and for example, a metal element such as gold, platinum,nickel, palladium, cobalt, selenium, and vanadium, or alloys thereof,and metal oxides such as tin oxide, zinc oxide, indium tin oxide (ITO)and indium zinc oxide can be used. Conductive polymers such aspolyaniline, polypyrrole, polythiophene and polyphenylenesulfide canalso be used. These electrode substances may be used alone and two ormore of them can also be used in combination.

On the other hand, as a cathode material, those having a low workfunction is suitable and a metal element such as lithium, sodium,potassium, calcium, magnesium, aluminum, indium, silver, lead, tin andchromium or alloys of two or more thereof can be used. Use of a metaloxide such as indium tin oxide (ITO) is also possible. The cathode maybe in a single layer structure or can take a multilayer structure.

Substrate used in the present invention is not limited, but anon-transparent plate such as metal substrate and ceramics substrate, atransparent plate such as glass, quartz, and a plastic sheet can beused. It is also possible to use a color filter film, a fluorescentcolor conversion filter film, a dielectric reflective film, etc. on thesubstrate to control the color of the emitted light.

In addition, a protection layer or seal layer can also be provided onthe formed device in order to prevent contact with oxygen, moisture,etc. The protection layer may include inorganic material films such as adiamond thin film, a metal oxide film and a metal nitride film, polymerfilms such as those of a fluororesin, polyparaxylene, polyethylene,silicone resin and polystyrene resin as well as light curable resin,etc. Moreover, the device may be covered with glass, a gas impermeablefilm, metal, etc., and the device itself may be packaged in a suitablesealing resin.

Hereainfter, the present invention will be described by non-limitingexamples still more specifically.

EXAMPLE 1 Preparation Process of Example Compound No. [1]-43

2 g (6.25 mmol) of 2-iodo-9,9-dimethylfluorene and 1.5 g (4.12 mmol) of2-(dihydroxyboranyl)-9,9-dimethylfluorene were dissolved in the mixedsolvent (80 ml of degassed toluene and 40 ml of ethanol) and agitatedunder nitrogen flow, and 41 ml of sodium carbonate solution which wasprepared by dissolving 9 g of anhydrous sodium carbonate in 45 ml ofwater was added dropwise thereto. After agitating for 30 minutes, 238 mg(0.206 mmol) of tetrakis(triphenylphosphine) palladium was added.Heating with agitation was carried out on the oil bath heated at 80° C.for about 5 hours. After cooling the reaction solution to roomtemperature, 50 ml of water and 50 ml of ethyl acetate were added, theaqueous layer and the organic layer were separated, the aqueous layerwas further extracted with toluene and ethyl acetate, and the extractcombined with the above organic layer was dried over magnesium sulfate.The solvent was evaporated, the residual substance was refined by silicagel column chromatography (toluene:hexane=1:2), and 1.5 g ofbis(9,9-dimethylfluorene) was obtained.

4.2 g (10.9 mmol) of bis(9,9-dimethylfluorene), 1.38 g (5.43 mmol) ofiodine and 0.5 g of 50% sulfuric acid were dissolved in 80 ml ofmethanol and agitated with heating on the oil bath heated at 60° C., andabout 1 g of 35% by weight aqueous hydrogen peroxide was added dropwisethereto. After cooling the reaction solution to room temperature, 30 mlof water was added and the deposited crude crystal was separated byfiltration. The crude crystal was refined by silica gel columnchromatography (toluene:hexane=1:2), and 5.0 g of monoiodide ofbis(9,9-dimethylfluorene) was obtained.

113 mg (0.2 mmol) of palladium bis(benzylideneacetone) and 120 mg (0.6mmol) of tri-tert-butylphosphine were dissolved in 40 ml of tolueneunder nitrogen flow, and agitated at room temperature for 15 minutes.1.02 g (2 mmol) of monoiodide of bis(9,9-dimethylfluorene) dissolved in50 ml of toluene was added dropwise thereto, and agitated for 30minutes. 0.59 g (3 mmol) of bis(4-methylphenyl)amine dissolved in 50 mlof toluene was also added dropwise thereto, and subsequently 0.43 g (4.5mmol) of sodium tert-butoxide was added. Heating with agitation wascarried out on the oil bath heated at 120° C. for about 8 hours. Aftercooling the reaction solution to room temperature, 50 ml of water wasadded, the aqueous layer and the organic layer were separated, theaqueous layer was further extracted with toluene and ethyl acetate, andthe extract combined with the above organic layer was dried overmagnesium sulfate. The solvent was evaporated, the residual substancewas refined by silica gel column chromatography (toluene:hexane=1:2),and 0.93 g of example compound [1]-43 was obtained.

EXAMPLE 2 Preparation Process of Example Compound No. [1]-60

1.02 g (2 mmol) of monoiodide of bis(9,9-dimethylfluorene) and 0.97 g (3mmol) of bis(4-methylphenyl)aminobenzene-4-boronic acid were dissolvedand agitated under nitrogen flow in the mixed solvent (140 ml ofdegassed toluene and 70 ml of ethanol), and 30 ml of sodium carbonatesolution which was prepared by dissolving 6 g of anhydrous sodiumcarbonate in 30 ml of water was added dropwise thereto. After agitatingfor 30 minutes, 174 mg (0.15 mmol) oftetrakis(triphenylphosphine)palladium was added. Heating with agitationwas carried out on the oil bath heated at 80° C. for about 5 hours.After cooling the reaction solution to room temperature, 70 ml of waterand 70 ml of ethyl acetate were added, the aqueous layer and the organiclayer were separated, the aqueous layer was further extracted withtoluene and ethyl acetate, and the extract combined with the aboveorganic layer was dried over magnesium sulfate. The solvent wasevaporated, the residual substance was refined by silica gel columnchromatography (toluene:hexane=1:2), and 1 g of example compound [1]-60was obtained.

EXAMPLE 3 Preparation Process of Example Compound No. [2]-40

6.94 g (21.7 mmol) of 2-iodo-9,9-dimethylfluorene and 1 g (7.25 mmol) of1,4-phenylenebis(boronic acid) were dissolved and agitated undernitrogen flow in the mixed solvent (120 ml of degassed toluene and 60 mlof ethanol), and 145 ml of sodium carbonate solution which was preparedby dissolving 30 g of anhydrous sodium carbonate in 150 ml of water wasadded dropwise thereto. After agitating for 30 minutes, 840 mg (0.727mmol) of tetrakis(triphenylphosphine) palladium was added. Heating withagitation was carried out on the oil bath heated at 80° C. for about 3hours. After cooling the reaction solution to room temperature, 50 ml ofwater and 50 ml of ethyl acetate were added, the aqueous layer and theorganic layer were separated, the aqueous layer was further extractedwith toluene and ethyl acetate, and the extract combined with the aboveorganic layer was dried over magnesium sulfate. The solvent wasevaporated, the residual substance was refined by silica gel columnchromatography (toluene:hexane=1:2), and 3.02 g of1,4-phenylenebis(9,9-dimethylfluorene) was obtained.

5.04 g (10.9 mmol) of 1,4-phenylenebis(9,9-dimethylfluorene), 1.38 g(5.43 mmol) of iodine and 0.5 g of 50% sulfuric acid were dissolved in120 ml of methanol. Heating with agitation was carried out on the oilbath heated at 60° C., and about 1 g of 35 wt % aqueous hydrogenperoxide was added dropwise thereto. After cooling the reaction solutionto room temperature, 30 ml of water was added and the deposited crudecrystal was separated by filtration. The crude crystal was refined bysilica gel column chromatography (toluene:hexane=1:2), and 5.9 g ofmonoiodide of 1,4-phenylenebis(9,9-dimethylfluorene) was obtained.

1.18 g (2 mmol) of monoiodide of 1,4-phenylenebis(9,9-dimethylfluorene)and 0.97 g (3 mmol) of bis(4-methylphenyl)aminobenzene-4-boronic acidwere dissolved and agitated under nitrogen flow in the mixed solvent(100 ml of degassed toluene and 50 ml of ethanol), and 30 ml of sodiumcarbonate solution which was prepared by dissolving 6 g of anhydroussodium carbonate in 30 ml of water was added dropwise thereto. Afteragitating for 30 minutes, 174 mg (0.15 mmol) oftetrakis(triphenylphosphine)palladium was added. Heating with agitationwas carried out on the oil bath heated at 80° C. for about 5 hours.After cooling the reaction solution to room temperature, 60 ml of waterand 60 ml of ethyl acetate were added, the aqueous layer and the organiclayer were separated, the aqueous layer was further extracted withtoluene and ethyl acetate, and the extract combined with the aboveorganic layer was dried over magnesium sulfate. The solvent wasevaporated, the residual substance was refined by silica gel columnchromatography (toluene:hexane=1:2), and 1.09 g of example compound[2]-40 was obtained.

EXAMPLE 4

The organic light-emitting device of the structure shown in FIG. 3 wasprepared by the process shown below.

A glass substrate as the substrate 1 on which a film of indium tin oxide(ITO) having a film thickness of 120 nm as the anode 2 was formed bysputtering method was used as a transparent conductive supportsubstrate. This substrate was subjected to ultrasonic washing in acetoneand isopropyl alcohol (IPA) subsequently, boil-washed in IPA and dried.It was further subjected to UV/ozone washing and used as a transparentconductive support substrate.

The compound shown by the following structural formula was used as ahole-transporting material and a chloroform solution thereof wasadjusted so that the concentration thereof was 0.5% by weight.

This solution was dropped on the above ITO electrode (anode 2), and spincoating was performed first by rotation at 500 RPM for 10 secondsfollowed by rotation at 1000 RPM for 1 minute to form a film. It wassubsequently dried in a vacuum oven at 80° C. for 10 minutes, and thesolvent in the thin film was removed completely. The thickness of theformed TPD film (hole-transporting layer 5) was 50 nm.

Next, vacuum evaporation of the above-mentioned example compound No.[1]-43 was carried out to deposit the compound on the hole-transportinglayer 5, and the 20 nm-thick light-emitting layer 3 was formed. Thedegree of vacuum at the time of vacuum evaporation was 1.0×10⁻⁴ Pa, andthe film forming speed was 0.2 to 0.3 nm/sec.

Furthermore, aluminum quinolinol (Alq3) was formed into a film of 40 nmin thickness as an electron-transporting layer 6 by vacuum evaporationmethod. The degree of vacuum at the time of the vacuum evaporation ofthese organic layers was 1.0×10⁻⁴ Pa, and the film forming speed was 0.2to 0.3 nm/sec.

Next, using the vacuum evaporation source material consisting of analuminum-lithium alloy (lithium concentration 1 atom %), a metal filmwith a thickness of 10 nm was formed by vacuum evaporation method on theabove organic layer, the aluminum film with a thickness of 150 nm wasfurther prepared by vacuum evaporation method, and the organiclight-emitting device comprising an aluminum-lithium alloy film as anelectron injection electrode (cathode 4) was prepared. The degree ofvacuum at the time of vacuum evaporation was 1.0×10⁻⁴ Pa, and the filmforming speed was 1.0 to 1.2 nm/sec.

The obtained organic EL device was covered with a glass plate forprotection in dry air atmosphere, and sealed with an acrylic resin basedadhesive so that the device might not be degraded by adsorption ofmoisture.

6V was applied to the thus obtained device by using an ITO electrode(anode 2) as a positive electrode and an Al—Li electrode (cathode 4) asa negative electrode. As the result, and blue luminescence of 780 cd/m²of luminance, maximum luminance of 5900 cd/m², and luminescenceefficiency 0.73 lm/W were observed.

EXAMPLES 5 TO 13

Devices were formed in the same way as in Example 4 except that examplecompound [1]-43 was replaced with the example compounds shown in Table14 and evaluated in the same way. The results are shown in Table 14.

TABLE 14 Example Applied Maximum compound voltage Luminance luminanceEfficiency Example No. (V) (cd/m²) (cd/m²) (1m/W) 5 [1]-16 7 680 50000.57 6 [1]-49 6 880 6700 0.75 7 [1]-60 6 840 6100 0.83 8 [1]-92 6 9006600 0.77 9 [1]-95 6 1000  6800 0.85 10   [1]-158 6 820 6400 0.72 11 [2]-17 6 820 5700 0.80 12  [2]-65 6 980 6800 0.87 13  [2]-85 6 810 59000.68

EXAMPLE 14

A device was formed in the same way as in Example 4 except that examplecompound No. [1]-60 and example compound No. [3]-1 were co-deposited(5:100 in weight ratio) to form 20 nm-thick light-emitting layer 3.

6V was applied to the thus obtained device by using an ITO electrode(anode 2) as a positive electrode and an Al—Li electrode (cathode 4) asa negative electrode. As the result, blue luminescence of 4200 cd/m² ofluminance, maximum luminance of 9600 cd/m², and luminescence efficiency1.20 lm/W were observed.

EXAMPLES 15 TO 23

Devices were formed in the same way as in Example 10 except that examplecompound [1]-60 was replaced with the example compounds shown in Table15 and evaluated in the same way. The results are shown in Table 15.

TABLE 15 Example Applied Maximum compound voltage Luminance luminanceEfficiency Example No. (V) (cd/m²) (cd/m²) (1m/W) 15 [1]-6  7 2900  65000.67 16 [1]-47 6 6800 17200 1.74 17 [1]-49 6 6300 16600 1.62 18 [1]-80 65100 11500 1.30 19 [1]-91 6 5200 13100 1.42 20 [1]-99 6 6900 16500 1.8021 [2]-17 6 4600 11700 1.28 22 [2]-65 6 6100 14200 1.52 23 [2]-85 6 510011900 1.39

EXAMPLE 24

A device was formed in the same way as in Example 4 except that examplecompound No. [1]-43 and example compound No. [3]-15 were co-deposited(5:100 in weight ratio) to form 20 nm-thick light-emitting layer 3.

6V was applied to the thus obtained device by using an ITO electrode(anode 2) as a positive electrode and an Al—Li electrode (cathode 4) asa negative electrode. As the result, blue luminescence of 3900 cd/m² ofluminance, maximum luminance of 10500 cd/m², and luminescence efficiency1.12 lm/W were observed.

EXAMPLE 25

A device was formed in the same way as in Example 24 except that examplecompound No. [1]-43 was replaced with example compound No. [2]-40.

The thus obtained device along with an ITO electrode (anode 2) as apositive electrode and an Al—Li electrode (cathode 4) as a negativeelectrode was used on the applied voltage of 6 V, and blue luminescenceof 4200 cd/m² of luminance, maximum luminance of 13100 cd/m², andluminescence efficiency 1.125 lm/W were observed.

EXAMPLE 26

A device was formed in the same way as in Example 4 except that examplecompound No. [1]-92 and example compound No. [4]-1 were co-deposited(5:100 in weight ratio) to form 20 nm-thick light-emitting layer 3.

6V was applied to the thus obtained device by using an ITO electrode(anode 2) as a positive electrode and an Al—Li electrode (cathode 4) asa negative electrode. As the result, blue luminescence of 6000 cd/m² ofluminance, maximum luminance of 12200 cd/m², and luminescence efficiency1.45 lm/W was observed.

EXAMPLES 27 TO 30

Devices were formed in the same way as in Example 26 except that examplecompound No. [1]-92 was replaced with the example compounds shown inTable 6 and evaluated in the same way. The results are shown in Table16.

TABLE 16 Example Applied Maximum compound voltage Luminance luminanceEfficiency Example No. (V) (cd/m²) (cd/m²) (1m/W) 27 [1]-66 6 5600 118001.33 28  [1]-158 6 3900  9800 1.17 29 [2]-17 6 5300 14100 1.47 30 [2]-656 6600 15400 1.61

EXAMPLE 31

A device was formed in the same way as in Example 4 except that examplecompound No. [1]-60 and the above-mentioned example compound No. [5]-1were co-deposited (5:100 in weight ratio) to form 20 nm-thicklight-emitting layer 3.

6V was applied to the thus obtained device by using an ITO electrode(anode 2) as a positive electrode and an Al—Li electrode (cathode 4) asa negative electrode. As the result, blue luminescence of 4500 cd/m² ofluminance, maximum luminance of 13700 cd/m², and luminescence efficiency1.35 lm/W were observed.

EXAMPLE 32

A device was formed in the same way as in Example 31 except that examplecompound No. [1]-60 was replaced with example compound No. [2]-40.

6V was applied to the thus obtained device by using an ITO electrode(anode 2) as a positive electrode and an Al—Li electrode (cathode 4) asa negative electrode. As the result, blue luminescence of 4900 cd/m² ofluminance, maximum luminance of 15200 cd/m², and luminescence efficiency1.45 lm/W were observed.

EXAMPLE 33

A device was formed in the same way as in Example 4 except that examplecompound No. [1]-60 and example compound No. [6]-2 were co-deposited(5:100 in weight ratio) to form 20 nm-thick light-emitting layer 3.

6V was applied to the thus obtained device along with an ITO electrode(anode 2) as a positive electrode and an Al—Li electrode (cathode 4) asa negative electrode. As the result, blue luminescence of 4700 cd/m² ofluminance, maximum luminance of 15800 cd/m², and luminescence efficiency1.65 lm/W were observed.

EXAMPLE 34

A device was formed in the same way as in Example 33 except that examplecompound No. [6]-2 was replaced with example compound No. [6]-9.

6V was applied to the thus obtained device by using an ITO electrode(anode 2) as a positive electrode and an Al—Li electrode (cathode 4) asa negative electrode. As the result, blue luminescence of 5900 cd/m² ofluminance, maximum luminance of 18200 cd/m², and luminescence efficiency1.85 lm/W were observed.

EXAMPLE 35

A device was formed in the same way as in Example 4 except that examplecompound No. [1]-92 and the above-mentioned example compound No. [7]-1were co-deposited (5:100 in weight ratio) to form 20 nm light-emittinglayer 3.

6V was applied to the thus obtained device by using an ITO electrode(anode 2) as a positive electrode and an Al—Li electrode (cathode 4) asa negative electrode. As the result, blue luminescence of 5100 cd/m² ofluminance, maximum luminance of 12300 cd/m², and luminescence efficiency1.38 lm/W were observed.

EXAMPLES 36 TO 43

The luminescence spectra of the devices formed in Examples 4, 15, 21,26, 31, 33, 34 and 35 were observed by MCPD-7000 and the CIEchromaticity coordinates were measured. The results are shown in Table17.

TABLE 17 CIE chromaticity coordinate Example Device example No. (x, y)36  4 0.15, 0.10 37 15 0.15, 0.10 38 21 0.15, 0.11 39 26 0.15, 0,10 4031 0.16, 0.10 41 33 0.15, 0.09 42 34 0.15, 0.09 43 35 0.15, 0.11

EXAMPLE 44

A device was formed in the same way as in Example 4 except that examplecompound No. [7]-1 and example compound No. [2]-65 were co-deposited(5:100 in weight ratio) to form 20 nm-thick light-emitting layer 3.

6V was applied to the thus obtained device by using an ITO electrode(anode 2) as a positive electrode and an Al—Li electrode (cathode 4) asa negative electrode. As the result, blue luminescence of 4700 cd/m² ofluminance, maximum luminance of 11100 cd/m², and luminescence efficiency1.30 lm/W were observed.

EXAMPLE 45

A device was formed in the same way as in Example 4 except that examplecompound No. [1]-43 and example compound No. [2]-65 were co-deposited(5:100 in weight ratio) to form 20 nm-thick light-emitting layer 3.

6V was applied to the thus obtained device by using an ITO electrode(anode 2) as a positive electrode and an Al—Li electrode (cathode 4) asa negative electrode. As the result, blue luminescence of 5900 cd/m² ofluminance, maximum luminance of 12600 cd/m², and luminescence efficiency1.39 lm/W were observed.

EXAMPLE 46

Voltage was applied to the device formed in Example 13 for 100 hoursunder nitrogen atmosphere while maintaining the current density at 7.0mA/cm² and degradation in luminance was found to be small as the initialluminance of 480 cd/m² was changed to 420 cd/m² after 100 hours.

COMPARATIVE EXAMPLE 1

A device was formed in the same way as in Example 4 except that thefollowing styryl compound was used as a light-emitting layer.

10V was applied to the thus obtained device by using an ITO electrode(anode 2) as a positive electrode and an Al—Li electrode (cathode 4) asa negative electrode. As the result, greenish blue white luminescence of120 cd/m² of luminance, maximum luminance of 3800 cd/m², andluminescence efficiency 0.17 lm/W were observed.

COMPARATIVE EXAMPLE 2

A device was formed in the same way as in Example 4 except that theabove styryl compound and example compound No. [4]-1 were co-deposited(5:100 in weight ratio) to form 20 nm-thick light-emitting layer 3.

10V was applied to the thus obtained device along with an ITO electrode(anode 2) as a positive electrode and an Al—Li electrode (cathode 4) asa negative electrode. As the result, greenish blue white luminescence of125 cd/m² of luminance, maximum luminance of 4500 cd/m², andluminescence efficiency 0.30 lm/W were observed.

COMPARATIVE EXAMPLE 3

The luminescence spectrum of the device formed in Comparative Example 2was observed by MCPD-7000 and the CIE chromaticity coordinate measuredwas (x,y)=(0.16, 0.30).

As described by way of embodiments and examples, the organiclight-emitting device using the monoaminofluorene compound representedby the general formula [1] or [2] of the present invention, used in asingle layer or in a mixed layer of dopant/host, enables high luminanceluminescence when applied with a low voltage and is also excellent incolor purity and durability. Furthermore, the device can be formed usingvacuum evaporation, the casting method or the like, and a device havinga large area can be readily produced at a relatively low cost.

1. A monoaminofluorene compound selected from the following compounds:


2. A monoaminofluorene compound selected from the following compounds:


3. An organic light-emitting device comprising: a pair of electrodeswhich consist of an anode and a cathode, and one or more layers whichare interposed between the electrodes and contain an organic compound,wherein at least one of the layers containing the organic compound is alight-emitting layer and contains at least one of the followingcompounds:


4. An organic light-emitting device comprising: a pair of electrodeswhich consist of an anode and a cathode, and one or more layers whichare interposed between the electrodes and contain an organic compound,wherein at least one of the layers containing the organic compound is alight-emitting layer and contains at least one of the followingcompounds:


5. The organic light-emitting device according to claim 3, wherein thelayer containing the organic compound contains at least one additionalcompound represented by the following general formula [3]:

where Ar₁ to Ar₃ may be the same or different and are groups selectedfrom the group consisting of substituted or unsubstituted aryl andheterocyclic ring groups, and either one of them may be a hydrogen atom,a substituted or unsubstituted alkyl group, or a substituted orunsubstituted aralkyl group; and

where Ar₄ to Ar₇ may be the same or different and are groups selectedfrom the group consisting of substituted or unsubstituted aryl andheterocyclic ring groups; and R₁₀ and R₁₁ are groups selected from thegroup consisting of a hydrogen atom, a halogen group, substituted orunsubstituted alkyl and aralkyl groups, a substituted amino group and acyano group.
 6. The organic light-emitting device according to claim 4,wherein the layer containing the organic compound contains at least oneadditional compound represented by the following general formula [3]:

where Ar₁ to Ar₃ may be the same or different and are groups selectedfrom the group consisting of substituted or unsubstituted aryl andheterocyclic ring groups, and either one of them may be a hydrogen atom,a substituted or unsubstituted alkyl group, or a substituted orunsubstituted aralkyl group; and R₇ to R₉ are groups selected from thegroup consisting of a hydrogen atom, a halogen group, substituted orunsubstituted alkyl and aralkyl groups, a substituted amino group and acyano group.
 7. The organic light-emitting device according to claim 3,wherein the layer containing the organic compound contains at least oneadditional compound represented by the following general formula [4]:

where Ar₈ to Ar₁₂ may be the same or different and are groups selectedfrom the group consisting of substituted or unsubstituted aryl andheterocyclic ring groups; and R₁₂ is a group selected from the groupconsisting of a hydrogen atom, a halogen group, substituted orunsubstituted alkyl, aralkyl, aryl and heterocyclic ring groups, asubstituted amino group and a cyano group.
 8. The organic light-emittingdevice according to claim 4, wherein the layer containing the organiccompound contains at least one additional compound represented by thefollowing general formula [4]:

where Ar₄ to Ar₇ may be the same or different and are groups selectedfrom the group consisting of substituted or unsubstituted aryl andheterocyclic ring groups; and R₁₀ and R₁₁ are groups selected from thegroup consisting of a hydrogen atom, a halogen group, substituted orunsubstituted alkyl and aralkyl groups, a substituted amino group and acyano group.
 9. The organic light-emitting device according to claim 3,wherein the layer containing the organic compound contains at least oneadditional compound represented by the following general formula [5]: R₇to R₉ are groups selected from the group consisting of a hydrogen atom,a halogen group, substituted or unsubstituted alkyl and aralkyl groups,a substituted amino group and a cyano group.
 10. The organiclight-emitting device according to claim 4, wherein the layer containingthe organic compound contains at least one additional compoundrepresented by the following general formula [5]:

where Ar₈ to Ar₁₂ may be the same or different and are groups selectedfrom the group consisting of substituted or unsubstituted aryl andheterocyclic ring groups; and R₁₂ is a group selected from the groupconsisting of a hydrogen atom, a halogen group, substituted orunsubstituted alkyl, aralkyl, aryl and heterocyclic ring groups, asubstituted amino group and a cyano group.
 11. The organiclight-emitting device according to claim 3, wherein the layer containingthe organic compound contains at least one additional compoundrepresented by the following general formula [6]:

where Ar₁₃ to Ar₁₆ may be the same or different and are groups selectedfrom the group consisting of substituted or unsubstituted aryl andheterocyclic ring groups, and up to any three of them may be a hydrogenatom, a halogen group, a substituted or unsubstituted alkyl group and asubstituted or unsubstituted aralkyl group; and R₁₃ to R₁₆ are groupsselected from the group consisting of a hydrogen atom, a halogen group,substituted or unsubstituted alkyl, aralkyl, aryl and heterocyclic ringgroups, a substituted amino group and a cyano group.
 12. The organiclight-emitting device according to claim 4, wherein the layer containingthe organic compound contains at least one additional compoundrepresented by the following general formula [6]:

where Ar₁₃ to Ar₁₆ may be the same or different and are groups selectedfrom the group consisting of substituted or unsubstituted aryl andheterocyclic ring groups, and up to any three of them may be a hydrogenatom, a halogen group, a substituted or unsubstituted alkyl group and asubstituted or unsubstituted aralkyl group; and R₁₃ to R₁₆ are groupsselected from the group consisting of a hydrogen atom, a halogen group,substituted or unsubstituted alkyl, aralkyl, aryl and heterocyclic ringgroups, a substituted amino group and a cyano group.
 13. The organiclight-emitting device according to claim 3, wherein the layer containingthe organic compound contains at least one additional compoundrepresented by the following general formula [7]:

where R₁₇ and R₁₈ are groups selected from the group consisting of ahydrogen atom and substituted or unsubstituted alkyl, aralkyl and arylgroups, and R₁₇ and R₁₈ bound to different fluorene moieties may be thesame or different and R₁₇ and R₁₈ bound to the same fluorene moiety maybe the same or different; and R₁₉ to R₂₂ are groups selected from thegroup consisting of a hydrogen atom, a halogen group, substituted orunsubstituted alkyl and aralkyl and alkoxy groups, a substituted silylgroup and a cyano group; and s is an integer of 2 to
 5. 14. The organiclight-emitting device according to claim 4, wherein the layer containingthe organic compound contains at least one additional compoundrepresented by the following general formula [7]:

where R₁₇ and R₁₈ are groups selected from the group consisting of ahydrogen atom and substituted or unsubstituted alkyl, aralkyl and arylgroups, and R₁₇ and R₁₈ bound to different fluorene moieties may be thesame or different and R₁₇ and R₁₈ bound to the same fluorene moiety maybe the same or different; R₁₉ to R₂₂ are groups selected from the groupconsisting of a hydrogen atom, a halogen group, substituted orunsubstituted alkyl and aralkyl and alkoxy groups, a substituted silylgroup and a cyano group; and s is as integer of 2 to 5.